This naming issue is so widespread that most users would not recognize what GNU is, even if they are using a GNU/Linux operating system. I recently read an article that referred to GNU Bash as “Linux’s Bash”; this is simply a slap in the face to all the hackers that have for the past 26 years been writing what is one of today’s most widely used shells on Unix-like systems (including on Apple’s proprietary Mac OSX), and all the other GNU hackers.
When users talk about “Linux” as the name of the operating system, they avoid talking about GNU. And by avoiding mention of GNU, they are also avoiding discussion of the core principles upon which GNU is founded—the belief that all users deserve software granting four essential freedoms: the freedom to use the program for any purpose; the freedom to study the program and modify it to suit your needs (or have someone do it on your behalf); the freedom to share the program with others; and the freedom to share your changes with others. We call software that respects these four freedoms free/libre software.